FR2997411A1 - Composition in form of gel coat used as non-skid coating, comprises liquid polymer without solvent, aggregates, optionally pigments, mineral fillers, additives and components constituted of e.g. carbon nanotubes and micrometer sized fibers - Google Patents

Abstract

The invention relates to the field of the manufacture of paints, coatings and functional coatings and more particularly to a composition in the form of a gelled coating or a thixotropic liquid suitable for use as a non-slip coating after combination and chemical reaction with a reactive polymer (hardener), containing one or more liquid polymers without solvent, at least two different types of anti-slip aggregates, optionally pigments, mineral fillers and various additives, characterized in that it comprises in in addition to: - the first nanoscale components consisting of carbon nanotubes Note: 1) should the protection be extended to the use of a single type of aggregate? 2) Should we extend the protection to all types of nanoscale NTC fibers but also ???

Description

The subject of the present invention is polystructured anti-slip coating compositions intended more particularly for the protection of ship decks, in particular flight decks for aircraft carriers and helicopter carriers, this application not being limiting. The technical field of the invention is that of the manufacture of paints, coatings and functional coatings. Ship bridges, including aircraft doors, as well as, for example: bridges for offshore oil rigs and research platforms, walkways or traffic lanes for handling equipment in workshops or stores, shuttle floors and vehicle transport wagons, the soils of nuclear power plants, are subject to multiple and repeated causes of abrasion and impact and require very strong cohesive coatings to withstand the multiple causes of abrasion, cracking, and all kinds of physico-chemical aggressions, if we want to avoid frequent repairs and achieve maintenance savings. In addition, these coatings must be highly slip-resistant and retain this property for as long as possible and under multiple environmental conditions. Experience shows that the need for anti-slip coatings is increasing year by year and that the labor costs of setting up and maintaining them are very high. The multilayer antiskid device described in the patent application FR2585357 is known. It comprises at least one anticorrosive printing layer, covered with at least one anti-slip thick layer, which layers each comprise a base containing a crosslinkable resin and a hardener, characterized in that said bases contain hydroxylated vinyl terpolymers which are copolymers of vinyl chloride, of vinyl esters and of hydroxylated esters with reactive hydroxyl groups and said hardeners contain an aromatic or aliphatic polyisocyanate dissolved in organic solvents, so that layers based on crosslinked polymers known as "polyvinyl urethanes".

However, this type of coating has the disadvantage that, in order to provide it with the thixotropic properties necessary for a satisfactory operation, the maintenance of the anti-slip aggregates in regular suspension until the end of the process of setting up and crosslinking, and a long storage stability, it is necessary to combine specific additives such as bentonites or modified hydrogenated castor oil (HRH) with more or less polar organic solvents (ketones, hydrocarbons, esters. However, the use of organic solvents has become, from the point of view of hygiene and safety and from the point of view of the impact on the environment, extremely penalizing, regulated and even very often prohibited in many locations. In addition, from a technical point of view, there is regularly a certain retention of solvents in the dry film at low setting temperatures, which causes a significant loss of mechanical performance and adhesion to the support. The object of the invention is to provide a polystructured anti-slip coating having strongly thixotropic properties necessary for the maintenance of anti-slip aggregates in suspension without the use of organic solvent. The solution provided is, according to a first characteristic, a composition in the form of a gelled coating or a thixotropic liquid suitable for use as an anti-slip coating after combination with a reactive polymer generally called a hardener, this composition comprising a base containing a or more liquid polymers without solvent, at least two different types of anti-slip aggregates, optionally pigments and various additives and being characterized in that it further comprises: a first type of component consisting of fibers of nanometric size, consisting of by carbon nanotubes; a second type of component comprising fibers of micrometric size and / or a third type of component comprising millimeter-sized fibers. By fiber, is meant an element whose width or diameter is small relative to its length, their ratio being typically less than 0.1. Nanometric size means that the diameters of the nanotubes are of the order of one nanometer, namely between 5 and 200 nm, while their length may be between 100 nm and 20 μm. By micron size means that the diameters of the microfibers or their width are of the order of a micrometer, namely between 0.5 and 100 pm, while their length may be between 10 and 1000 pm. By millimetric size, it is meant that the lengths of these fibers are between 0.1 mm and 20 mm, while their diameter or their width is between 100 μm and 2 mm. In the following, gelled coatings and thixotropic liquids will be called coatings. The first and second components provide the composition with both strong thixotropy and long-term storage stability, allowing suspension aggregates to remain in suspension throughout the initiation process and throughout the crosslinking phase. and hardening of the coating, which is necessary to obtain the desired anti-slip characteristics, and provide the coating once crosslinked, unique mechanical properties such as a very strong internal cohesion, a very high resistance to impacts and cracking and a considerable reduction of friability. The second components may for example comprise glass microfibers and / or polyaramid and / or carbon or graphite, or pulps based on these microfibers or a mixture of these components.

These thixotropic properties can be further improved by incorporation of the third millimeter-sized components which may comprise, for example, glass fibers, thermoset polymer fibers, glass threads cut from carbon fibers or cut carbon threads or a mixture of these. components.

According to another characteristic, the polymer base is a polyurethane precursor (polyols of the polyester type, polyethers, polyacrylates) or of a hydroxylated polysiloxane polymer, which can then be crosslinked, for example with a hardener such as a solvent-free aliphatic polyisocyanate to obtain a solid crosslinked coating.

The anti-slip aggregates may, depending on the locations concerned, for example be based on hard aluminum alloy, aluminum oxide, quartz powder, ceramic powders, glass powder, boron carbide, or thermoset polymer powders, etc.

According to one particular characteristic, the composition comprises, by weight, from 0.001 to 15% of nanoscale first component, namely carbon nanotubes and from 0.01 to 20% of the second micrometric size components comprising, for example, microfibres of glass and / or polyaramid and / or carbon or graphite, or pulps based on these microfibers.

According to an additional feature, the composition comprises, by weight, from 0.01 to 30% of third millimeter components comprising, for example, glass fibers, thermoset polymer fibers, cut glass or carbon fibers or carbon fibers or carbon fibers. graphite. The invention also relates to a kit comprising a composition according to the invention and a separate hardener capable of reacting chemically with this composition to form a solid coating. The invention also relates to a hardener capable of reacting chemically with a composition according to the invention to form a crosslinked solid coating, characterized in that it comprises fibers of nanometric size, for example carbon nanotubes. The invention also relates to a non-slip coating comprising a polymer matrix comprising non-slip aggregates and optionally pigments, mineral fillers and / or additives, and characterized in that it further comprises: first-sized components nanometric carbon nanotubes (CNTs) - second micrometric size components comprising, for example, glass and / or polyaramide and / or carbon or graphite microfibres, or pulps based on these microfibers, and preferably, millimeter-sized third components comprising, for example, glass fibers, thermoset polymer fibers, chopped glass strands or carbon or graphite fibers. In the case of an aircraft carrier, it is found that the wear of a non-slip coating is not uniform over the entire deck. Thus, at the level of the steel cables able to retain the aircraft during their landing, the wear of the coating is extremely fast, and due firstly to the friction of the cable on the coating and secondly to the shocks of the decking rod on the coating. In addition, these rubs cause premature wear of the steel cables.

Therefore, it is proposed to use a particular type of coating at these cables. Table 1 shows four examples of gelled coating compositions suitable for use as a non-slip coating after combination with a reactive polymer (hardener). Each of these coatings comprises two different polyols, for example a polyether and a polyester, or a polyacrylate: the advantage of using a mixture of two or more polyols is to obtain a crosslinked network of polymers of different molecular weights and different distributions of functional groups on their chains, which contributes to obtain crosslinked networks of different meshes and nested in each other, which can only contribute to the optimization of the mechanical and chemical properties of the matrix. In addition these polyols may provide different properties, one of the polyols may for example provide elasticity, another the hardness or resistance to UV, etc. The catalysts are well known in the state of the art. They intervene at the level of the crosslinking (polycondensation polymerization in this case) and allow the crosslinking to start at a lower temperature. Adjuvants, also called additives, are well known in the state of the art. Dispersants, matting agents, anti-UV agents, anti-bubble agents, leveling agents, surfactants, hydrophobic agents, etc. may be used as examples. The mineral fillers are well known in the state of the art: for example, mica, micaceous iron oxide, talc, calcium carbonate and the like can be used. Flame retardants are well known in the state of the art. For example, compounds based on polyphosphates can be used. Opacifying dyes are well known in the art. There may be mentioned mineral dyes such as titanium dioxide, iron oxides, etc. or organic dyes such as those based on phthalocyanine or carbon black.

For generally used aggregates such as aluminum powders, glass powders, aluminum oxide powders, quartz powders, etc. for example, a particle size of between 200 and 500 micrometers for type 1 and between 500 and 1500 micrometers for type 2 can be used. Coatings 1, 3 and 4 each comprise first components of nanometric size, second components of micrometric size and third components of millimeter size while the second coating 2 does not have millimeter-sized fibers. Coating 1 Coating 2 Coating 3 Coating 4 Component% by weight% by weight% by weight% by weight Polyol resin 1 15 20 20 10 Polyol resin 2 5 0 0 10 Predispersed carbon nanotubes (nanometric fibers) 3 5 4 2 Micrometric fibers 3 6 4 5 Millimeter fibers 5 0 6 5 Flame retardant 5 5 5 7 Opacifying pigments 10 12 10 9 Mineral fillers 12 10 10 10 Admixtures and / or catalysts 2 2 1 2 Anti-slip aggregates 1 aluminum alloy (Granulometry 1) Non-slip aggregates 2 of aluminum alloy (particle size 2) Table 1 Table 2 shows four examples of hardeners according to the invention capable of being mixed with the coatings of Table 1 to form a mixture suitable for being applied on a ship deck and then cross-linked and dried to form the anti-slip coating.

The aromatic polyisocyanates crosslink at a lower temperature than the aliphatic polyisocyanates but turn yellow with UV. Their mixture allows to benefit from the advantages of one and the other while reducing the associated disadvantages. Also, depending on the meteorological conditions and / or the possibility of or not heating the coating / hardener mixture, or the importance or otherwise of the yellowing of the coating due to UV, one will rather use one or the other of hardener formulations. For example the use can be the following: - hardener 1: warm temperature of the environment or possibility of heating the mixture and no yellowing, - hardener 2: fresh temperature of the environment and no possibility of sufficiently heating the mixture and the yellowing of the coating does not matter or the coating is UV protected, Hardener 3: average temperature and acceptance of a slight yellowing Hardener 4: average temperature and acceptance of a yellowing or protected coating. The presence of NTC makes it possible to obtain an even more homogeneous and therefore more resistant coating and also to improve the thixotropic nature of the hardener. Hardener 1 Hardener 2 Hardener 3 Hardener 4 Component% by weight% by weight% by weight% by weight Aliphatic polyisocyanate 99 0 80 50 Aromatic polyisocyanate 0 99 19 49 Predispersed carbon nanotubes 1 1 1 1 Table 3 shows four examples of coatings can be used as a coating after being mixed with a hardener such as for example one of those shown in Table 2. Compared to the coating compositions shown in Table 1 those of the coatings of Table 3 are essentially different in that that the material of the aggregates is different, namely harder and their average proportion is higher, the mineral load is then a little lower. Coating 1 Coating 2 Coating Coating Component% by weight% by weight% by weight% by weight Polyol resin 1 14 18 19 11 Polyol resin 2 5 0 0 9 Predispersed carbon nanotubes (nanometric fibers) 3 5 4 2 Micrometric fibers 3 6 3 5 Millimeter fibers 5 0 5 5 Flame retardant agent 6 5 5 7 Mineral opacifying pigments 10 10 11 9 Mineral filler 7 9 5 5 Adjuvants and / or catalysts 2 2 1 2 Non-slip ceramic aggregates 1 (particle size 1) Ceramic Non-Slip Adhesives 2 (Particle Size 2) Table 3 Table 2 The methods of making the compositions according to the invention are quite similar to those used in the manufacture of current non-slip coating compositions.

A rapid disperser such as for example Cowles helices is used to homogeneously mix and disperse the additives, the pigments and the nanometric components in the base containing the polymer precursors: this rapid dispersion may, in certain cases, require a rise in the temperature of the base up to about 80 ° C to facilitate the development of the thixotropic character. Then, a kneader is used to incorporate the anti-slip aggregates, the microfibers and possibly the third millimeter components. The composition thus obtained is then packaged in a first container, the hardener is packaged in a second container.

For the implementation of the anti-slip coating can be proceeded as follows: It is possible, if necessary to deposit beforehand on the substrate to cover, for example the deck of a ship, previously stripped or blasted, one or more layer of anticorrosive paint adapted to improve the attachment of the non-slip coating. This application can for example be carried out by spray, airless or roller. Then, while respecting the times of recovery of the anti-corrosion layers, the anti-slip coating is prepared by mixing a hardener according to the invention or according to the state of the art to a composition according to the invention, then the mixture is applied, for example to using a trowel, a roller or a spatula, on the substrate possibly covered by said anticorrosive layers. It is then sufficient to allow the coating to cure and cure for about 24 to 72 hours, depending on the ambient temperature, until optimum mechanical strength and physical properties are achieved before commissioning. Of course, the compositions in Tables 1 to 3 are given by way of non-limiting examples, a composition according to the invention may for example comprise one or more liquid polymers without solvent, at least one type of anti-slip aggregates, optionally pigments, mineral fillers and various additives, and being characterized in that it further comprises: first nanoscale components; second components consisting of micron-sized fibers and / or third components consisting of millimeter size.

Claims (11)

REVENDICATIONS1. Composition in the form of a gelled coating or a thixotropic liquid suitable for use as an anti-slip coating after combination and chemical reaction with a reactive polymer (hardener), comprising one or more liquid polymers without solvent, at least two different types of anti-slip aggregates, optionally pigments, mineral fillers and various additives, characterized in that it further comprises: first nanoscale components, constituted by carbon nanotubes; second components consisting of micrometric sized fibers and / or third components made of millimeter sized fibers. 2. Composition according to claim 1, characterized in that it comprises second components comprising microfibres of glass and / or polyaramid and / or carbon or graphite, or pulps based on these microfibers. 3. Composition according to any one of claims 1 and 2, characterized in that it comprises third millimeter-sized components comprising glass fibers, thermoset polymer fibers, cut glass yarns, or fiberglass fibers. carbon. 4. Composition according to any one of claims 1 to 3, characterized in that the polymer base is a polyurethane precursor or a polysiloxane polymer. 30 5. Composition according to any one of claims 1 to 4, characterized in that the anti-slip aggregates are based on hard aluminum alloy, aluminum oxide, quartz powder, ceramic powders, glass powder, boron carbide, or thermoset polymer powders. 6. Composition according to any one of Claims 1 to 5, characterized in that the composition comprises, by weight, from 0.001 to 15% of decarbon nanotubes and from 0.01 to 20% of second micrometric size components comprising, for example, microfibres of glass and / or polyaramid and / or carbon or graphite, or pulps based on these microfibres, 7. Composition according to any one of claims 1 to 6, characterized in that the composition comprises, by weight, from 0.01 to 30% of third millimetric components comprising, for example, glass fibers, thermoset polymer fibers, cut glass or carbon fiber or graphite. 8. Kit comprising a composition according to any one of claims 1 to 7 and a separate hardener capable of reacting chemically with this composition to form a crosslinked solid coating. 9. Hardener chemically reactive with a composition according to any one of claims 1 to 7 to form a crosslinked solid coating, characterized in that it comprises nanoscale fibers, for example carbon nanotubes. 10. Non-slip coating comprising a polymer matrix comprising at least two types of non-slip aggregates and optionally pigments and additives, and characterized in that the matrix further comprises: nanoscale first nanoscale components carbon, - second components made of micron-sized fibers, for example comprising glass and / or polyaramide and / or carbon or graphite microfibers, or pulps based on these microfibers. 11. Non-slip coating according to claim 10, characterized in that it further comprises third "millimeter" components comprising glass fibers, thermoset polymer fibers, cut glass yarns, or carbon fibers or carbon fibers. graphite.